Is registration required?
vDos is largely freeware, even open source. It will however check if the PC is joined to a domain, or files on a network drive are addressed. Only if so, the About popup is then displayed every three hours of continuous use. That eventual popup can be clicked away, without consequences for vDos’ functionality. If vDos isn’t used that often, this shouldn’t pose a real obstacle. Though vDos is also sort of mild nagware for some targeted business users. A registration or donation would of course still be appreciated, even if the popup/nag doesn’t apply.
What will it bring?
That nag won't show up anymore. You would contribute to rewarding the countless hours invested in vDos, further development and support; keep vDos nag-free for most users? You'll be informed of new versions. Some two weeks after the initial release, so eventually reported bugs will be fixed. Registered users however generally don't care about new vDos versions. The current one obviously does the job… I could be more open to your specific issues or wishes, and supply an intermediate pre-release to address those.
What about new versions?
Registration is lifetime and remains valid for any new versions. If I would decide to change this policy, it won’t involve existing registrations.
How to register?
After filling out the registration form, you’ll receive an e-mail with an invoice and license file (if paid directly by Stripe). The license file is to be copied to the vDos directory. That’s it, no further activation procedures or online validations. Transferring a registered vDos to other/new systems, remains a copy of some files (plus one).
vDos can be registered in two flavours, they only differ in what vDos eventually checks for:
User name: € 35 per user name.
The Windows user name has to be (one of) the user name(s) defined in the license file.

Networked: € 150.
The number of users is unlimited, as long the PC’s are joined to the registered domain or that network drive is addressed.

The required user name(s) or network ID for registration are shown in the nag, System Menu - About… in a framed vDos window, or issuing the
ABOUT command at the vDos/DOS command prompt.
Money back guarantee?
No, you can (should) evaluate vDos for as long you feel needed to be confident it will fulfill your requirements. A vDos license can’t be revoked since there is no online validation. It will remain valid for the registered (future) edition it applies to.